Basically. If it is too fast of an action the treble hooks will consistently rip out of the fish, and if is too slow you won't be able to set the hook hard enough to punch through a halibut's mouth. Moderate or Mod fast may seem to be slow, but they actually have the best blend of hook setting power and "cushioning" to prevent the hooks from ripping out. They also load up and cast the Lucky Crafts the better than other rods.